M. is not to be confused, as HOLLIS does, with the better-known cardinal Marcantonio Colonna (c. 1523–1597). The latter was the archbishop of Salerno from 1568 to 1574, when he resigned the see in favor of M. who was probably his relative. DBI. M. lacks a modern biographer, but Zedler described him as the son of Cornelio Marsilli and Lavinia Colonna of Bologna, who died in Camerino in 1589 at the age of 47. There is no particular reason to doubt that he is the author of De ecclesiasticorum reddituum origine et iure tractatus, published in Venezia in 1555 (we have seen WorldCat references to an earlier edition in Lyon in 1550), nor the description on the title page of the 1555 ed. that the author is then the archbishop of Salerno. We might wonder what the publisher meant when he describes the author as ‘iuris consultus’. The work is more one of church history than it is of church law, though the presence of some citations of jurists suggests that the author may have had some legal training. To him are also ascribed a collection of synodal statutes for Salerno, published in Napoli in 1580, a Libellus de vita et gestis B. Matthaei apostoli et evangelistae, ejusque gloriosi corporis in Salernitanam urbem translatione also in Napoli in 1580, and Hydragiologia siue de aqua benedicta, published in Roma in 1586, and which also describes him as ‘iuris consultus’.